The problem occurs due to a known issue with Click-to-Run registry virtualization.

Protection PLUS 4 SDK users may see error 46 returned from any Protection PLUS 4 SDK function that attempts to write a value to the Windows Registry.Protection PLUS 5 SDK users (particularly when using writable license files and aliases) may receive errors such as 9219 (only when using PLUSNative) or 9201 from functions that attempt to write a value to the Windows Registry.Instant Protection PLUS 3 users may see their licensed applications fail to run after displaying an Error 46 message.When licensed software is running in Microsoft Office 2013 or later in a Click-to-Run deployment, the following may occur: This can occur even if you properly set the permissions for the values written to the Windows Registry. When Microsoft Office is installed via a Click-to-Run deployment, you may experience issues with Microsoft Office add-ins or macros that use Protection PLUS features that write values to certain areas of the Windows Registry. Office 2013 and Office 2016 Click-to-Run compatibility issues with Protection PLUS Summary of the problem

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